Confusion about 2nd law of thermo

In summary, entropy and energy have different units - kJ/kg K for entropy and kJ for energy. While entropy may not be conserved, energy is conserved in a system due to the presence of another form of energy that decreases as entropy increases. This form of energy is typically free energy, but there may be other categories as well. This concept can be likened to the value of beef, which increases when the price per pound increases, even though the mass of the beef remains the same. Similarly, in a system, the total value of energy remains constant even if its form may change.
  • #1
nate9519
47
0
Entropy has units of kJ/kg K and energy has units of kJ. So my question is if entropy is not conserved how is energy conserved when there is a unit of energy within entropy?
 
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  • #2
Hi nate:

In a system in which entropy increases, there will be another form of energy in the system which is decreasing so that the total energy is conserved. Generally this will be free energy, but AFAIK there technically might possibly be another category of energy other than "free energy" which would decrease as entropy increased.
See https://en.wikipedia.org/wiki/Free_energy .

Regards,
Buzz
 
  • #3
If you have 90 lb of beef at $5/lb, the value of the beef is $450. Now the price goes up to $10/lb, and the value increases to $900. How come, if the value of the beef contains the mass of the beef as a factor, and mass is conserved, why isn't the value of the beef conserved?
 

1. What is the second law of thermodynamics?

The second law of thermodynamics states that the total entropy of a closed system will always increase over time, or remain constant in ideal cases where the system is in a state of equilibrium or undergoing a reversible process.

2. What is the difference between the first and second law of thermodynamics?

The first law of thermodynamics, also known as the law of conservation of energy, states that energy cannot be created or destroyed, only converted from one form to another. The second law, on the other hand, focuses on the direction of energy transfer and the increase in entropy over time.

3. How does the second law of thermodynamics relate to everyday life?

The second law of thermodynamics explains why, in our daily lives, we experience things like the natural flow of heat from hot to cold objects, the gradual decay of materials, and the tendency for systems to become more disordered over time. It also plays a crucial role in understanding energy efficiency and the limitations of perpetual motion machines.

4. Can the second law of thermodynamics be violated?

No, the second law of thermodynamics is a fundamental law of nature and has never been observed to be violated. It has been extensively tested and confirmed through numerous experiments and observations.

5. How does the second law of thermodynamics apply to the universe?

The second law of thermodynamics applies to the entire universe, as it states that the total entropy of a closed system will always increase or remain constant. This means that over time, the universe will become increasingly disordered and will eventually reach a state of maximum entropy, also known as the heat death of the universe.

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